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Much ado about nothing: the 30 minute guide to the universe NYSS-AAPT meeting SUNY - Brockport October 1, 2005 [email protected] http://www.pas.rochester.edu/~manly/ The intimate relationship between the very big and the very small Inquiring minds want to know ... Yo! What holds it together? Fermi National Accelerator Laboratory (near Chicago) CDF Minos Stanford Linear Accelerator Center Event display from the SLD experiment at SLAC What forces exist in nature? What is a force? How do they interact? How do forces change with energy or temperature? How has the universe evolved? Force Gravitation Source mass Range infinite Strength -39 10 Electromagnetism Electric charge Strong nuclear Color charge Weak nuclear Weak charge infinite 10-2 10 -15 10 -18 m m 1 10 -5 qqq Baryons - proton,neutron Mesons - pion, kaon qq Mini-Ph.D. – Quantum Mechanics 101 Lesson 1: Size actually does matter. Determine the postion and velocity of a car … no problem Determine the postion and velocity of a small particle … no problem Problem! Heisenberg uncertainty principle Cannot have perfect knowledge of both the position and velocity Heisenberg The fundamental nature of forces: virtual particles Et h e- Heisenberg E = mc2 Einstein qq e+e+e+ e ee e+ee+eqq e+eqq Much ado about NOTHING: qq qq qqqq qq e+eNothing is something qq qq +eqqNothing has energy + e +ee e + e ee +ee + e ee+einteracts Nothing with something qq +ee qq qq qq qq qq -R. Kolb The essence of inertial mass at the quantum level (quantum field theory) qqq qq qqq qqq qqq qq On to the very big … Telescopes are time machines 1 Mpc= 1 Megaparsec = 3x1022 m 1 light year = 9x1015 m Light travels from NYC to San Francisco in 1/100 second …. and it travels 1 Mpc in 3 million years Edwin Hubble (1889-1953) discovers a surprise in 1929 Galaxies that are further away appear redder Apparent Doppler shift -From webphysics.davidson.edu Light travels from NYC to San Francisco in 1/100 second …. and it travels 1 Mpc in 3 million years Welcome to the “expanding universe”!! extrapolate back in time find the age of the universe 13 billion years. Type Ia SNe from Riess, Press and Kirshner (1996) -MSSL astrophysics group Cosmic Microwave Background Penzias and Wilson - 1964 Uniform and isotropic – in as far as they could measure BANG! TIME Very hot, dense primordial soup of fundamental particles At 0.000001 second after bang, protons and neutrons form At 3 minutes, light nuclei form At ~300,000 years, t = 3000 degrees, atoms form and light streams freely t=~13 billion years, Ben Affleck and Jennifer Lopez break up Modern accelerators study processes at energies that existed VERY early in the universe Another form of time travel ! What were forces like at those temperatures? What types of particles existed? Many, many missing pieces … How can the universe be so isotropic? How did the structure (galaxies, clusters of galaxies) arise?? Do we know about all of the fundamental particles that exist? Why 3 families? Why is the mass spectrum of fundamental particles as it is? Why is the universe matter instead of antimatter? Recent progress! But new puzzles… -R. Kolb We seem to be missing most of the mass in the universe! -P. Cushman Very exciting development in last decade Observed fluctuations in the CMB temp WMap data on the temperature fluctuations in the CMB why structure matters Einstein’s field equations: the modern laws of Genesis -R. Kolb One possible future of the universe End of universe Buffalo wins the Superbowl Hell freezes over Sun burns out Today Million- billion years 1000 billion years 100 billion years 17 billion years 12 billion years time -R. Kolb “Power spectrum” (size) of temperature fluctuations sensitive to different matter/energy components of the universe WMAP composition of the universe ~1/20 W = WM + WL = WB + WDM + WL -P. Cushman The elusive neutrino mass Mass eigenstates (3 or more) 1 2 3 4 e + target e- + X Flavor eigenstates – relevant for weak interaction with other particles + target - + X + target - + X The elusive neutrino Quantum mechanical mixing of states: |> = ΣiU*i|i> Weak flavor eigenstate Mass eigenstate Unitary leptonic mixing matrix Analogous to CKM matrix for quarks Neutrino with momentum p evolves with time: |(t)> = ΣiU*i|i>e-iEi(p)t/h Neutrino of definite flavor is a superposition of several mass eigenstates whose different masses cause them to propagate differently changing the mixture of the mass eigenstates, i.e. neutrino oscillations in vacuum Solar neutrino puzzle Solar neutrinos (only e produced in core of sun) Homestake Mine, Davis et al. 100,000 Gal tetrachloroethylene 37Cl 37Ar e(Homestake)/e(theory) ~ 0.34+-0.06 Homestake only sensitive to high E tail of e flux Fisher, Kayser, McFarland, Ann. Rev. Nucl. Part. Sci. 49, (1999) 481. Neutrinos physics in the last decade Sudbury Neutrino Observatory (SNO) 1000 metric tons of D2O in 12 m acrylic vessel sund e sune e 0.15 sund e SNO: e+=5.44+-0.99x106 cm-2s-1 Bahcall: total ~ 5.05x106 cm-2s-1 SNO: e/(total ) ~ 0.34 Neutrinos oscillate and have mass … solar puzzle solved! Neutrinos physics in the last decade SuperKamiodande 50,000 tons of pure H2O Atmospheric neutrinos Cosmic rays interact in atmosphere and produce e and neutrinos Accelerator neutrinos K2K experiment M.H. Ahn et al., PRL 90 (2003) 041801 Reactor neutrinos KamLAND experiment D. Eguchi et al., PRL 90 (2003) 021802 Evidence for a sterile neutrino? MiniBooNE results in late summer or early fall … The future Long baseline Two detectors – one near, one far High statistics – challenge for accelerator and detector On and off axis Need to minimize systematic errors Videos from ATLAS Collaboration website Large Hadron Collider (LHC) SuperNova Acceleration Probe We live in exciting times! Thanks to: Priscilla Cushman, CDMS, G-2, Univ. of Minnesota Rocky Kolb, Fermilab and University of Chicago Stanford Linear Accelerator Center CERN, European Center for Particle Physics Fermi National Accelerator Laboratory Brookhaven National Laboratory Davidson University webphysics project WMAP project Hubble Space Telescope project Ned Wright, UCLA MSSL astrophysics group Newton, Einstein, Heisenberg, Plank, etc. And whoever else I forgot to mention …